Device for gapping slide fasteners



Feb. 13, 1968 M. PERLMAN 3,368,269

DEVICE FOR GAPPING SLIDE FASTENERS Filed Dec. 2, 1965 United States Patent Office 3 368,269 DEVICE FOR GAPiING SLIDE FASTENERS Morris Perlman, 1326 38th St., Brooklyn, NY. 11218 Filed Dec. 2, 1965, Ser. No. 511,116 3 Claims. (Cl. 29-207.5)

ABSTRACT OF THE DISCLOSURE A gapping device for slide fasteners comprising a lower stationary bifurcated die member and an upper clamping block displaceable vertically of the die member. The die member is formed with sharp edge portions at the upper portions of the bifurcated surfaces. A vertically displaceable punch is brought down on slide fastener tape clamped to the die. The punch impacts the slide fastener coils against the die and severs these. During its continuing downward travel, the punch member pulls the severed coil portions into a suitable receptacle.

My invention relates to a device for gapping slide fasteners in continuous slide fastener chains.

In the manufacture of the individual lengths of slide fasteners from a continuous slide fastener chain, a group of fastener elements comprising a pair of interengaged coil filaments are cut and excised from the chain to form a filament-free gap, thereby forming the element-free gap for the top end of the slide fastener and the element-free gap for the bottom end of the next slide fastener.

The devices now in use suffer from a serious disadvantage in that during the cutting and excising operation, minute sharp particles of the slide fastener elements remain in the filaments and cause abrasions of the human skin with which the slide fastener frequently comes in contact.

An important object of my invention, therefore, is to provide a slide fastener gapping device which will cut the fastener in a clean manner without leaving sharp particles or loose coil parts in the tapes at the gaps, thus effecting a scrapiess cutting operation.

Another object of the invention is to provide a device of the above character which is rapid and efficient in operation, simple in construction and which may be easily serviced.

These and other important objects of the invention will become apparent from the following description and the accompanying drawing illustrating a preferred embodiment of the invention.

It should be understood, however, that these given by way of illustration and not of limitation, and that various changes in the details, form and arrangement of the parts may be made without departing from the scope of the invention.

In the drawings:

FIG. 1 is a perspective view, partly in section of the essential parts the device employed in practicing the invention;

FIG. 2 is a partial cross-sectional view, showing one stage of the operation of the device;

FIG. 3 is a view similar to FIG. 2, showing another stage of operation of the device;

FIG. 4 is a view similar to FIG. 3, showing yet another stage of the operation of the device;

FIG. 5 is a view similar to that of FIG. 4 showing still another stage of the operation of the device;

FIG. 6 is an enlarged view of a pair of coil sections of the slide fastener after these have been cut by the device;

FIG. 7 illustrates a part of the device, in cross-section, used with another type of slide fastener tape and FIG. 8 is a sectional view of a modified punch.

Patented Feb. 13, 1968 Referring now to the drawing in detail, the gapping device according to the invention, generally indicated as 10, comprises a lower bifurcated die block 12, cooperating with a cutting punch 14. Aligned with the lower die block 12 and spaced above it is an upper vertically displaceable bifurcated block 16 for holding and guiding the slide fastener tape 18. Block 12 is rigidly mounted on a frame (not shown) of a slide fastener gapping machine. Disposed above the upper block 16 is a vertically displaceable plate 20, which is guided on bolts 22, 22a secured to the movable upper bifurcated block 16 and is normally held in spaced parallel relationship with block 16 by helical springs. A rod 26, rigidly secured to the plate 20, is displaceable vertically by appropriate means, thereby displacing in an up and down direction bifurcated block 16, the plate 20 and the punch 14, which is rigidly secured to said plate and guided in slot 28 of the guide block 16. The punch 14 is formed with an arcuate end 29. The thickness of the punch is dimensioned in such a manner that the spaces between either of the side faces 30, 30a and the faces 32, 32a of the bifurcated lower block 12 are narrower than the thickness of the coils 34, 34a of the coil filaments 36b.

The faces 32, 32a of the block 12 terminate as sharp edge portions 36, 36a and, like the punch 14, these portions are made of hard steel or any abrasion-resistant material. Both blocks 12 and 16 are formed with guide recesses 38, 38a and 40, 40a for guiding the coils 34, 34a of the slide fastener filaments 36.

In FIGS. 1, 2, 3, 4, and 5, the slide fastener tape 18 is of the type having edges 42, 42a which overlie partly the coils 34, 34a. In this instance these filament coils are guided in the recesses 40, 40a.

As shown in these figures, the device operates as follows:

After the slide fastener tape 18 has been forwarded into position for the gapping operation, the plate 20 is moved downward, first causing thereby the block 16 to clamp the tape 18 in position. As plate 20 continues its downward travel, the springs 24, 24a are compressed and the punch 14 is displaced downward from its initial position shown in FIG. 2. It will be noted that in this position the arcuate end 29 of the punch 14 is positioned centrally of the coils 34, 34a and partly between the edges 42 and 42a of tape 18. As the punch 14 continues its downward movement, the arcuate end 29 impacts the coils 34, 34a, thus deforming these, while, due to the pressure exerted by the punch, the edges 36, 36a cut the coils, as shown in FIG. 3.

As the punch 14 continues its downward stroke, it engages the now severed coil portions and pulls these down into the spaces between the faces 30, 30a of the punch and the faces 32, 32a of the bifurcated lower block 32. Due to the fact that these spaces are narrower than the thickness of the coils 34, 34a, the coil portions are engagiersi frictionally by the punch, as shown in FIGS. 4 an Upon retraction of the punch 14 and the guide and holdlng block 16 to their initial position (FIGS. 1, 2) the co l portions 33, 33a FIGS. 5 and 6, drop down into a suitable receptacle (not shown). Since the guide and holding block 16 is in the raised position, shown in FIG. 1, the tape 18 can now be fed into place for the next cutting operation.

To further improve the efiiciency of the gapping operation, the punch may be provided with notches 44, 44a, as shown in FIG. 8 which will engage and pull the coils downward after these have been cut.

As shown in FIG. '8, the gapping device may be employed for gapping slide fasteners wherein the filament coils 46, 46a are uncovered. The device may also be employed with any type of slide fasteners presently used.

3 4 I claim: tween the respective side faces of said punch member 1. A device for gapping a slide fastener tape having a and said walls being less than the cross-section of the pair of mating coils formed of a material having a prematerial forming the coils of the slide fastener tape, determined cross-section, comprising: said die member being further provided with recesses an upper clamping block having a central vertical slot 5 for the tape, said punch member being further disextending therethrough, said upper block being proplaceable in the slot of said lower die member. vided with a pair of threaded openings and circular 2. The device of claim 1, wherein the lower portion recesses surrounding said Openings, of said punch member is formed with an arcuate crossa pair of helical springs seated in said circular recesses, section.

3. The device of claim 1, wherein said side faces of the punch member are formed with notches for additiona horizontal plate disposed above said upper block and having a pair of bores therethrough, said springs 10 biasing said upper block and said late, ally engaging and pulling the coils in a downward direca pair of bolts secured with their threaded ends in said tiO threaded openings and extending through said springs Ref Ci d and said bores, a punch member rigidly secured to said plate and slid- 15 UNITED STATES PATENTS able through said central vertical slot in said upper 3,123,543 4/1964 a CiaII 29200 X block, said punch member having a pair of parallel 3,225,430 12/1955 FflSCiaIlO 0 5 X planar side faces defining said melnbers thickness, 3,273,229 1966 T ylor 29-200 21 lower die member having a slot therethrough aligned 20 with said punch member, the width of said slot being THOMAS H. EAGER, Primary Examiner. defined by a pair of parallel walls, the distance be- 

